THE STOCKLAND
HILL TRANSMITTER
is the UHF main station that serves Exeter and East Devon, as well
as some parts of Somerset and coastal areas of West Dorset. The
station also carries DAB and local FM radio services.

Sited near
Axminster and Honiton, it is the most easterly of the five
UHF main stations located across the south-west of England.
(See Regional
Map). The other UHF
main stations that serve the region are located at Beacon Hill (South Devon), Caradon
Hill (East Cornwall), Huntshaw Cross
(North Devon) and Redruth (West
Cornwall).

The station
is most associated historically with the Caradon
Hill transmitter due to the combined function of
both stations
in the establishment of ITV 405-line VHF coverage across the south-west
region. (See VHF Television
History)

Following
the successful completion of Digital Switchover at Beacon
Hill on 22 April 2009, Stockland Hill was the second transmitter
group in the south-west region to complete the process, which was implemented
in two stages as follows
-

Stockland Hill
was built by the Independent Television Authority (ITA) as one of
two 405-line VHF Band III stations required to establish an ITV
service across the south-western counties of Cornwall and Devon.

Propagation
tests ascertained that the 150-mile length of these two counties
combined was beyond the coverage capabilities of a single VHF Band
III station centrally-placed within Dartmoor, ruling out the possibility
of adjacent siting with the BBC VHF Band I station at North
Hessary Tor.

The ITA concluded
that separate stations would be required for Cornwall and Devon,
respectively positioned to the west and east of the Dartmoor Hills
and with both sited towards the east of their respective coverage
areas.

The Cornwall
station would utilise the Bodmin Moors as a means of ground
elevation, the chosen site being Caradon
Hill, near Launceston.

For the Devon
area transmitter, The Blackdown Hills provided the highest natural
platform and within this range Stockland Hill was identified as
a suitable site for the station. Somewhat characteristically
of the area, the site was located on a plateau rather than
a summit, with positioning almost immediately alongside the main
'Stockland Hill' road.

Scheduled to
transmit on VHF Channel 9, the principal service area of the station
needed to extend east-to-west from the respective borders
with Dorset and Somerset to parts of North Devon and crucially the
central ground of Dartmoor where coverage would link-up with that
of Caradon Hill to ensure a service
as
comprehensive as possible across this difficult territory.

Two vision
transmitters (both rated at 5 kilowatts) and two sound transmitters
(both rated at 1.25 kilowatts) were specified for the station.

Fairly typically,
a 750-ft (228 metre) mast was designated (as it was also at
Caradon Hill) to minimise the
negative impact of intervening hills. Combined with an identical
ground elevation, this provided an average aerial height of 1475-ft
(449 metres) above sea level.

The aerial
system was designed to deliver the maximum Effective Radiated Power
(e.r.p) of 100 kilowatts in two directions, north-west towards Barnstaple
and south-west towards Dartmouth. A minimal 10 kilowatts was
directed eastwards to negate the risk of interfering with the Croydon
station in London which also used VHF Channel 9. To provide
a mainland link to the Channel Islands, a 20 kilowatt signal
was beamed south-eastwards towards the link station at Alderney
for relaying to the Fremont Point transmitter, once this became
operational in September 1962.

Whilst designed
to minimise coverage duplication with adjacent stations, it
was accepted that fringe reception from Stockland Hill was
possible across much of Somerset despite the low power of eastward transmissions,
resulting in a notable overlap with the St Hilary (Cardiff) station.

Regular transmission from
both Caradon Hill and Stockland
Hill commenced on 29 April 1961 upon launch of the ITV service in
the south-west, the regional contractor being Plymouth-based Westward
Television.

The south-west
of England began the move to UHF colour in July 1969, initially
with BBC2 from Caradon Hill.
In total, five UHF main stations (plus numerous dependent
relays) were required across the region
with both Caradon Hill and Stockland
Hill as the principal components, as they had been for the
ITV 405-line service.

UHF Coverage
from Stockland Hill was typically curtailed in
comparison to the VHF service, despite an e.r.p of 250 kilowatts for UHF compared to 100 kilowatts
under VHF. Specifically, UHF was unable to match the far
north-westerly and south-westerly reaches
of the VHF signal, requiring the VHF relay site at Hunsthaw
Cross in North Devon to become a UHF main station (as
planned from the outset) and the construction of a totally new main transmitter site
at Beacon
Hill to cover South Devon.

Stockland Hill
commenced UHF-Colour transmission between 13 September 1971
and 2 October 1971, starting with ITV and completing with BBC2.
Although the station was manned, the ITV UHF transmitter fell
within the jurisdiction of the Colour Control Room (CCR) based at
Caradon Hill and later on the
Regional Operation Centre (ROC) at St Hilary.